Caenorhabditis elegans N-glycan Core β-galactoside Confers Sensitivity towards Nematotoxic Fungal Galectin CGL2

The physiological role of fungal galectins has remained elusive. Here, we show that feeding of a mushroom galectin, Coprinopsis cinerea CGL2, to Caenorhabditis elegans inhibited development and reproduction and ultimately resulted in killing of this nematode. The lack of toxicity of a carbohydrate-binding defective CGL2 variant and the resistance of a C. elegans mutant defective in GDP-fucose biosynthesis suggested that CGL2-mediated nematotoxicity depends on the interaction between the galectin and a fucose-containing glycoconjugate. A screen for CGL2-resistant worm mutants identified this glycoconjugate as a Galβ1,4Fucα1,6 modification of C. elegans N-glycan cores. Analysis of N-glycan structures in wild type and CGL2-resistant nematodes confirmed this finding and allowed the identification of a novel putative glycosyltransferase required for the biosynthesis of this glycoepitope. The X-ray crystal structure of a complex between CGL2 and the Galβ1,4Fucα1,6GlcNAc trisaccharide at 1.5 Å resolution revealed the biophysical basis for this interaction. Our results suggest that fungal galectins play a role in the defense of fungi against predators by binding to specific glycoconjugates of these organisms

Development and Applications of Transplastomic Plants; A Way Towards Eco-Friendly Agriculture

With distribution of genetic materials and advance molecular characteristics, the chloroplast is prokaryotic compartments within the eukaryotic plants that have turned into a crucial source for the genetic engineering and transplastomic plants are becoming more popular means of agricultural development with elevated crop yield. To address global agricultural problems, genetic modification of crop plants is a rapid and promising solution to adapt the environment-friendly and well-controlled farming system. The transplastomic plant with high accumulation of foreign proteins (up to 45-46% TSP) and stable transgene expression with gene containment can be a unique choice for the agricultural innovation of coming centuries. Although the transplastomic plants still facing encumber to ensure the full potential exploitation and expansion as an economical means, the removal of hardness and obstacles of this technology and commercialization can contribute for the sustainable development of future agriculture. In this book chapter, we intend to recapitulate the up to date development and achievement of transplastomic plant including gene transfer procedures in plastid genomes, regulable expression of plastid transgenes, plant trait improvement by foreign gene expression, biopharmaceuticals production, engineering of metabolic pathways in plant, study of transformation mediated RNA editing technologies, bio-safety issues and public concerns on transplastomic plants and overall beneficial aspects. We believe that the utilization of transplastomic plants will ensure an eco-friendly approach in agriculture with minimized hazards and public concerns. © Springer Nature Switzerland AG 2020